JPH10185972A - Antenna scan measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten time for measurement by speedily conducting an antenna scanning. SOLUTION: A stage put by measuring object 13 is continuously moved by rotational driving of a motor on an XY plane, the rotation of motor is detected by pulse Pm with a sensor 16 and the Pm is counted with a counter 17. The counting direction is controlled by a rotation direction signal S of the sensor 16 and the counted value of the counter 17 is transmitted to latches 21, 22 and 23 in turn at every clock as measured position of the stage 12. Each output of the counter 17 and the latches 21 to 23 is input in a calculation part 24 and the position (y) after measuring delay time τ of the measuring meter 18 is predicted with a recurrence formula and the measuring distance interval Δy are accumulated and added in a latch 33 at every trigger Tr . Then, the next measuring position of the latch 33 and (y) are compared with a compactor 34. If they coincide, a trigger Tr is generated and the measuring meter 18 starts measurement, and radiation amplitude phase of the objective 13 received by an antenna 14 is measured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used, for example, for measuring an unnecessary radiation source from an electronic circuit board, and two-dimensionally scans a measurement object with a measurement antenna to distribute the amplitude and phase of a radiated radio wave on the measurement object. The present invention relates to an antenna scanning measurement device for measuring the distance.

[0002]

2. Description of the Related Art A conventional device of this type is designed to measure an object to be measured in XY.
A measurement antenna is fixedly provided on a moving stage so as to face the object to be measured, and the stage is moved on the XY plane.
A dimensional scan was being performed. Conventionally, when acquiring measurement data at equal intervals in a scanning plane on a measurement object, the stage is stopped at each measurement point (position).

[0003]

Conventionally, the stage is stopped at each measurement position. Therefore, even if a high-speed moving stage is used, the moving speed cannot be sufficiently increased, and the high-speed stage has a high speed. I can't save it. For example, 25c
64 × 64 = 409 in the range of m × 25 cm at equal distance intervals
In the case of obtaining four points of measurement data, conventionally, one measurement required as much as 80 minutes.

[0004] It is an object of the present invention to provide an antenna scanning measuring apparatus capable of performing antenna scanning at a high speed and reducing the measuring time as compared with the conventional one.

[0005]

According to the present invention, the movement position of the stage is measured by the position measuring means, and the movement position of the stage after a measurement delay (trigger delay) time τ is determined by using the measured movement position. Is predicted by the prediction means,
When the predicted movement position becomes a position to be measured next to the stage, this is detected and a measurement command is generated by the trigger generation means.

In the predicting means, a constant of a regression equation of the predicted movement position using time as a variable is calculated using the measured movement position obtained at regular intervals, and the measurement delay time is added to the regression equation having the calculated constant. The predicted movement position is obtained by substituting τ.

[0007]

FIG. 1 shows an embodiment of the present invention.
The measurement object 13 is placed on the stage 12 of the XY movable stage device 11, and the measurement antenna 14 is fixed to face the XY moving surface of the measurement object 13. The stage 12 is moved in the XY plane by the rotation of the motor 15. In the figure, only a reciprocating mechanism in the X direction is shown, and although not shown, a reciprocating mechanism in the Y direction is also provided.

In the present invention, the movement position of the stage 12 is measured. In this embodiment, the rotation of the motor 15 is detected by a rotation sensor 16 as the position measuring means. That is, each time the motor 15 rotates a predetermined distance, that is, the stage 12 moves a predetermined distance, a pulse _Pm is output from the rotation sensor 16 and a direction signal S indicating the rotation direction of the motor 15 is output. The pulses _Pm are counted by the up / down counter 17, and the count is counted up or down by the direction signal S. When the stage 12 is moving in the positive direction, the counter 17 operates as an up counter, and when the stage 12 is moving in the negative direction, the counter 17 operates as a down counter. Twelve movement positions are obtained.

The signal received by the measuring antenna 14 is measured by a measuring device 18.
Is measured at the start of the measurement,
Since processing such as null measurement is required, a trigger delay time (measurement delay time) from when a measurement start trigger signal (measurement command) _Tr is applied to the measuring device 18 to when measurement is actually started.
τ exists. Therefore, in the present invention, the stage 12 is continuously moved, and τ is calculated using the measured movement position of the stage 12.
The movement position of the stage 12 after a time is predicted, and when the predicted movement position matches the position to be measured, a trigger signal (measurement command) _Tr is generated.

The predicted position is obtained by the following regression equation of the moving position y using the time t as a variable. _{y = a 0 + a 1 t} + a 2 t 2 + ... + a m t m (1) constant a _i of the equation (1) (i = 0,1, ..., m) is the measured moving position y _k at time t _k It is determined by solving the following determinant from n (0 < k < n).

[0011]

(Equation 1) In order to execute the operations of Expressions (1) and (2), the count value of the counter 17 is sequentially shifted to the latches 21, 22 and 23 by the clock from the clock generator 19. The output y _{3 of the} counter 17 and each y ₂ y ₁ y _{0 of} the latches 21, 22, and 23 are input to the regression formula calculation unit 24, and the delay time τ is further provided to the regression formula calculation unit 24 to obtain the formula (1). Is calculated, and the predicted movement position of the stage 12 at the time (t + τ) after τ time is obtained. In FIG. 1, the predicted position is obtained from the four measurement positions y _k , but it is sufficient that the past measurement movement position is one or more. For example, when only one latch 21 is used,
The two position data (y _k , t _k ) are (y ₀ , 0), (y
₁ , t ₁ ), and the predicted position y is obtained by a first-order regression equation. The constant _ai at this time is obtained by the following equation.

[0012] The predicted position y after the time τ is obtained by the following regression equation.

Y = a ₀ + a ₁ τ (4) If the regression equation calculation unit 24 that executes the equations (3) and (4) is configured by hardware, it can be easily realized by a product-sum operation as shown in FIG. 2A. . That is, the output y _{0 of the} latch 21 is inverted in polarity by the sign inverter 26, added to the output y _{1 of the} counter 17 by the adder 27, and the addition result a ₁ and τ are multiplied by the multiplier 28, The output y of the latch 21 is added to the result.
₀ = a ₀ is added by the adder 29 to obtain a predicted position y.

In this embodiment, the measured position and the predicted position are both determined with reference to the starting point of the stage. When the predicted position y coincides with the next measured position, a trigger signal _Tr is generated. That is, the measurement interval distance Δy is supplied to the adder 32 via the sign inverter 31 and the sign inverter 3
1 indicates that the sign reversal operation is stopped when the stage 12 is moving in the positive direction by the direction signal S from the rotation sensor 16 and only when the stage 12 is moving in the negative direction,
The sign is inverted, that is, −Δy is supplied to the adder 32. The adder 32 adds the output of the latch 33, that is, the next measurement position, and the added value is latched by the latch 33 every time the trigger signal _Tr is generated. That output of the sign inverter 31 for each trigger signal T _r ([Delta] y or -Derutawai) is cumulatively added to the output of the latch 33.

The next measurement position indicated by the latch 33 and the predicted position after τ time of the regression equation calculation unit 24 are compared by the comparator 34, and when the difference between them is 0 or the sign of the difference is inverted, the comparator 34 triggers. Generate signal _Tr . Therefore, the measurement of the measuring device 18 is started, and the data of the latch 33 is updated so as to indicate the next measurement position. The drive control of the XY stage device 11 by the motor 15 is performed by the control unit 35.
It is performed by

FIG. 2B shows another embodiment of the present invention, in which parts corresponding to those in FIG. 1 are denoted by the same reference numerals. In this example, for each measurement, both the measured movement position and the predicted movement position y of the stage 12 are set to zero. That is, the measurement position is set as a reference position for the next measurement position for each measurement. Therefore, the counter 17 is reset by the trigger signal _Tr . Predicted position y from regression equation calculation unit 24 and sign inverter 3
Δy or −Δy from 1 is compared by the comparator 34. Therefore, the adder 32 and the latch 33 are not required for the configuration shown in FIG.

In any of the embodiments, the measurement antenna 14 may be placed on the stage 12 and the measurement object 13 may be fixed.

[0018]

As described above, according to the present invention, the stage 12 is continuously moved, the movement position is predicted before the measurement delay (trigger delay) time .tau. Since the signal _Tr is generated,
The stage 12 is continuously moved without stopping at each measurement position, so that the high speed of the high-speed stage can be utilized, and the measurement time for one measurement target can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2A is a diagram showing a specific example of a regression equation calculation unit 24 in FIG. 1, and FIG. 2B is a block diagram showing another embodiment of the present invention.

Claims (4)

[Claims] 1. A measurement object and one of a measurement antenna for receiving a radio wave from the measurement object are fixed, the other is mounted on a stage, the stage is moved, and the measurement object is moved by the measurement antenna. In an antenna scanning measurement device for performing measurement by performing two-dimensional scanning, means for measuring a movement position of the stage, and using the measured movement position, a movement position of the stage after a measurement delay (trigger delay) time τ Antenna scanning, comprising: prediction means for predicting; and trigger generation means for detecting, when the predicted movement position becomes a position to be measured next to the stage to be measured next, and generating a measurement command. measuring device. 2. The prediction means calculates a constant of a regression equation of a predicted movement position using time as a variable by using the measured movement position obtained at regular intervals, and the regression equation having the calculated constant. 2. The antenna scanning measuring apparatus according to claim 1, further comprising means for calculating a predicted movement position by substituting the measurement delay time τ into the equation. 3. The apparatus according to claim 3, wherein the measured movement position and the predicted movement position are each based on a starting point of the stage, and each time the measurement command is issued, a means for cumulatively adding a measurement interval distance is provided. 3. The antenna scanning measuring apparatus according to claim 1, wherein the means is a means for detecting a coincidence between the accumulated value and the predicted movement position. 4. The measured moving position and the predicted moving position have a reference of zero for each measurement, and the trigger generating means is means for detecting a coincidence between the measurement interval distance and the predicted moving position. The antenna scanning measuring device according to claim 1 or 2, wherein: